Lionsgate Entertainment Corp. has struck back at a lawsuit filed over the opening-credits sequence of the hit series "Mad Men," claiming that the suit violates the company's First Amendment right to free speech.

In a motion to strike the complaint, lawyers for Lionsgate -- whose television division produces "Mad Men" -- argue that the opening sequence is "a creative work in its own right," and that "the protected free speech contained within the series and its opening title sequence relates to a public issue and an issue of public interest."

Gita Hall May, the model featured in the opening credits, filed her lawsuit in Los Angeles Superior Court in March. She claims that the sequence makes use of a Revlon ad that she appeared in, which was shot by photographer Richard Avedon in the 1950s. May contends that Lionsgate used the image without her permission, in violation of her right of publicity for commercial purposes.

"Because Defendants exploited the Photograph and Plaintiff's likeness and image while knowing that Defendants had no right to do so, and knowing that such conduct was a violation of Plaintiff's legal rights and the law, Defendants have acted with fraud, malice and oppression," the suit reads.

However, Lionsgate counters in its motion -- filed last Tuesday -- that Hall May's Revlon ad appears "for slightly more than one second" in the title sequence, and "has been altered and combined with dozens of other creatively altered images also taken from period advertisements and with new creative elements."

For those reasosn, Lionsgate argues, the sequence falls into the realm of constitutionally protected speech.